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Messages - BornFromTheVoid

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1
Arctic sea ice / Re: The 2020 melting season
« on: August 10, 2020, 11:55:54 PM »
Version 2. Getting there...

2
Arctic sea ice / Re: The 2020 melting season
« on: August 10, 2020, 10:20:26 PM »
Right on!  :)
That would be awesome!  ;D

I will need to use a different colour map to help the concentration data to stand out a bit more, and a few other adjustments to improve things. But here's a start at least.

3
Arctic sea ice / Re: The 2020 melting season
« on: August 10, 2020, 05:52:30 PM »

I added the last 24 hours to correct my mistake from before that the beaufort won't have too much damage inflicted on it. It sure looks like it was pretty windy there for a while.

I'm also wondering now if I wasn't wrong about the gap north of Greenland opening up more. Maybe until the pole? Wouldn't this crosswind open up that gap more instead of closing it? It would be good if BFTV could make an overlay with the ice to this. Would that be possible?

There's an error again on Nullschool that wouldn't go away.  >:(

Should be able to manage it. Will hopefully have it figured out soon!

4
Arctic sea ice / Re: The 2020 melting season
« on: August 10, 2020, 11:35:15 AM »
Below is the change in concentration from the 8th to the 9th of August. The second is the absolute change, where sea ice was lost or gained for the same dates.

5
Arctic sea ice / Re: The 2020 melting season
« on: August 10, 2020, 10:24:48 AM »
Close up of the Beaufort/Chukchi region over the last few days
(larger version on twitter: https://twitter.com/Icy_Samuel/status/1292737677608050691)

6
Arctic sea ice / Re: Arctic Image of the Day
« on: August 09, 2020, 03:13:01 PM »
The Vavilov Ice Cap, part of the Severnaya Zemlya archipelago in the Russian Arctic, producing some intriguing red sediment plumes this summer, something entirely absent last summer. Sentinel 2 images.
I'm guessing it's mostly derived from the red soil/rock that appears to dominate the area, and the ice and permafrost thaw from the Siberian heatwave.

7
Arctic sea ice / Re: The 2020 melting season
« on: August 09, 2020, 12:00:04 PM »
Concentration changes between the 7th and 8th, using University of Bremen data

8
Arctic sea ice / Re: The 2020 melting season
« on: August 08, 2020, 10:54:59 PM »
When I look at that, and then compare it to the DMI thickness map, I'm really starting to wonder if the DMI isn't a lot better than most people here thought. It's a perfect match in that area.

Might find this of use.

9
Arctic sea ice / Re: The 2020 melting season
« on: August 08, 2020, 11:16:57 AM »
First week of August, 2012 vs 2020
(Higher-res version on twitter: https://twitter.com/Icy_Samuel/status/1292026425348886529)

10
Arctic sea ice / Re: The 2020 melting season
« on: August 07, 2020, 10:32:13 PM »
An animation of the simple projections so far this melt season.

11
Arctic sea ice / Re: The 2020 melting season
« on: August 07, 2020, 10:25:16 AM »
That's a bit pedantic, Paul.

Okay it might be more consistent to stick with the one model, however scrollling through both ECMWF and GFS 2m anomalies over next few days both show very little +ve anomalies in the area BFTV has circled.  (If anything I would say GFS is more often the warmer at the 2m level over the Arctic basin).

But this is distracting from the main point of my post - not to confuse 850hPa with 2m temps.

850hPa temps are of course very useful for other reasons. So I cannot be sure exactly what BFTV's intention was. It could be said for example that the high 850hPa's are indicative of the presence of high pressure over the area of thickest ice.

Remember that over the ice the surface temperature will be pegged close to 0C due to the latent heat of fusion of ice, much like the 80N temps are. So you will not see strong +ve surface temperature values until the ice has melted, no matter how much heat is actually in the air.
As such, using 850hPa level (or 925hPa if available) in these situations works better for assessing ice thaw than surface level values.

12
Arctic sea ice / Re: The 2020 melting season
« on: August 06, 2020, 09:36:00 PM »
Almost impressive how focused the positive temperature anomalies are forecast to be for the next 5 days, right over the remaining thick ice.

13
Arctic sea ice / Re: The 2020 melting season
« on: August 06, 2020, 04:58:11 PM »
Latest projection now requires a recording breaking extent reduction to beat 2012. The average of the last 10 years produces the 5th lowest minimum, 4.16 million km2

14
Arctic sea ice / Re: The 2020 melting season
« on: August 06, 2020, 11:05:36 AM »
Animation of the Beaufort sea over the last 12 days.

15
Arctic sea ice / Re: The 2020 melting season
« on: August 06, 2020, 10:07:25 AM »
Detailed look at 7 days of ice movement and change on the north coast of Greenland.

(Larger file version here: https://twitter.com/Icy_Samuel/status/1291283817366421506)

16
Arctic sea ice / Re: Latest PIOMAS update (August 2020)
« on: August 04, 2020, 11:27:40 AM »
A focus on July and the larger picture.

Gap to lowest on record down to just 150 km3

17
Arctic sea ice / Re: The 2020 melting season
« on: August 04, 2020, 10:59:51 AM »
Change in the north of Greenland for the last 2 days

18
Arctic sea ice / Re: The 2020 melting season
« on: August 03, 2020, 03:30:09 PM »
North of Greenland, change from July 24th to August 2nd.
Higher-res version on here: https://twitter.com/Icy_Samuel/status/1290278384564465667

19
Arctic sea ice / Re: The 2020 melting season
« on: August 02, 2020, 12:21:24 PM »
Here's the difference between the concentration from the 31st of July and the 1st of August. Only the areas with change outside of -10% to +10% are coloured.

20
Arctic sea ice / Re: The 2020 melting season
« on: August 01, 2020, 09:51:08 PM »
Here's the video (gif was waaaay too big) of the concentration and MODIS data side by side for July. Let me know if there's any suggestions on improving it.

(Edit: Removed the video - didn't realise it was autoplaying. Here's a link instead:https://twitter.com/Icy_Samuel/status/1289672698361257984)

21
Arctic sea ice / Re: The 2020 melting season
« on: August 01, 2020, 12:37:51 PM »
Here's the final version of the comparison between the MODIS imagery and the concentration data. As usual, there's a higher-res version on the twitter page too: https://twitter.com/Icy_Samuel/status/1289510103733817344

I'll try put together a version, from a broader perspective, for the whole of July later on.

22
Arctic sea ice / Re: The 2020 melting season
« on: July 31, 2020, 08:12:30 AM »
An update on the side by side comparison. Those apparent concentration drops are looking more real than not.
Slightly higher res version on twitter, for those without data limits: https://twitter.com/Icy_Samuel/status/1289080922617372672

(Large file, click to play)

23
Arctic sea ice / Re: The 2020 melting season
« on: July 30, 2020, 05:54:12 PM »
Some of the concentration reductions are very real, some aren't. How much is real won't be apparent until we get more clear views.
Por ejemplo...

24
Arctic sea ice / Re: The 2020 melting season
« on: July 30, 2020, 01:07:41 PM »
As it appears (to my non-expert eyes) that clouds cause artifacts in the concentration products, the big question in my mind is whether they cause high-concentration streaks, or whether they cause low concentration streaks... Can some kind soul superimpose (and synchronize) the cyclone and the concentration images and prove it one way or the other?
p.s. Of course it's also possible the storm causes actual concentration changes that appear to be in its shape. Would love an expert opinion.

Another version, to add to uniquorns great work.

(Large file warning!)

25
Arctic sea ice / Re: The 2020 melting season
« on: July 30, 2020, 07:34:45 AM »
An update on the storm and concentration comparison. Higher res version on twitter.
https://twitter.com/Icy_Samuel/status/1288708042951929857

(click to play)

26
Arctic sea ice / Re: The 2020 melting season
« on: July 29, 2020, 10:30:48 PM »
Looks like a long lasting -ve dipole coming up. The pack will get spread out towards the Pacific and Siberian side. We will probably see extent continue fall at a slower than average rate for the next week, all while area continues to fall at a steady pace. June cliff 2.0?

5 day mean SLP with concentration overlayed below.


27
Arctic sea ice / Re: The 2020 melting season
« on: July 29, 2020, 06:44:20 PM »
Just 2 of the last 20 melt seasons now produce 2012-beating minimum.
16/20 would put 2020 at 2nd lowest on record.

28
Arctic sea ice / Re: The 2020 melting season
« on: July 29, 2020, 10:51:38 AM »
A side by side animation of the Arctic storm from MODIS worldview (mosaic for the 29th) with sea ice concentration. No concentration data yet for today, hence the blank right panel at the end.

I posted a higher res version on twitter too: https://twitter.com/Icy_Samuel/status/1288395604805267456

(Large file still, click to play)


29
Arctic sea ice / Re: The 2020 melting season
« on: July 28, 2020, 04:16:06 PM »
Now just 4 of the previous 20 melt seasons beat the 2012 minimum. However, all but 2 get 2020 down to 2nd lowest on record.

30
Arctic sea ice / Re: The 2020 melting season
« on: July 28, 2020, 12:53:47 PM »

There is a mistake with the left image. It's labeled 2012.

Nice catch, fixed!

31
Arctic sea ice / Re: The 2020 melting season
« on: July 28, 2020, 11:49:26 AM »
Concentration for the 26th, 27th and both combined.

32
Arctic sea ice / Re: The 2020 melting season
« on: July 27, 2020, 03:43:53 PM »
Side by side of July 26th in 2012 and 2020.

33
Arctic sea ice / Re: The 2020 melting season
« on: July 27, 2020, 03:07:26 PM »
In 2012, the storm took a little time to build in strength, and spread out the pack in the process causing a slight pause before the flash melt occurred. The ice around the Chukchi and ESS was much more sparse and broken compared to the Beaufort and Chukchi this year, so I don't think the slight pauses arise from the same process.

34
Arctic sea ice / Re: The 2020 melting season
« on: July 27, 2020, 11:41:19 AM »
Seems like the developing storm is pulling is the smoke/ash clouds from the Siberian wildfires. A risk of this getting deposited across the Beaufort and Chukchi ice.
https://twitter.com/Icy_Samuel/status/1287683902912503815

35
Arctic sea ice / Re: The 2020 melting season
« on: July 27, 2020, 09:23:07 AM »
Here's a comparison of the concentration averaged over the 23rd to the 25th, vs the concentration from the 26th.

36
Arctic sea ice / Re: The 2020 melting season
« on: July 26, 2020, 04:41:09 PM »
With the latest update, now just 5 of the previous 20 years would beat 2012, while the 10 year average would hit a low of 3.59 million km2.

Also, I've added a little video of the ice loss between June 30th and July 22nd below, but you can see it on my twitter account here also: https://twitter.com/Icy_Samuel/status/1287386145714839552

37
Arctic sea ice / Re: The 2020 melting season
« on: July 26, 2020, 11:16:55 AM »
Tuesday's storm potentially below 970hPa now, not quite GAC2012 but seemingly strengthening as we get closer.

38
Arctic sea ice / Re: The 2020 melting season
« on: July 25, 2020, 08:48:26 PM »
I put together a little animation using the GFS ensembles probability of 50km/h winds and the latest concentration map. (click to play)

39
Arctic sea ice / Re: The 2020 melting season
« on: July 25, 2020, 06:46:34 PM »
While extent has flat-lined over the last 2 days, the concentration continues to drop, especially in the Beaufort sea. It will be interesting to see how it deals with the low pressure early next week.
https://twitter.com/Icy_Samuel/status/1287065182452187136

40
Arctic sea ice / Re: The 2020 melting season
« on: July 23, 2020, 12:11:56 PM »
0z ECM and GFS in broad agreement on the weather to day 4/5, a variable mix of high and low pressure and a broad pattern favouring dispersion.
After that, ECM allows a deep low to take hold with some potentially stormy conditions, while the GFS produces a reverse dipole with a strong Atlantic to Pacific air flow.

06z GFS coming out now, so interesting to see where that goes

https://twitter.com/Icy_Samuel/status/1286225443776081920

41
Arctic sea ice / Re: The 2020 melting season
« on: July 21, 2020, 08:22:19 PM »

I have a quibble with these sorts of projections: They don't take into account the patterns of melt. Virtually every season rather closely follows a few overall patterns, and virtually every melt season has the specific pattern that the slope of the line in the first half of July continues into mid- or late August. Just tagging on the melt from this point on onto the end of 2020 is not likely to capture the actual potential outcome.

I largely agree. The projections I post are simple and naive, not meant in terms of any genuine scientific pursuit. Every melt season is different - every year the ice is configured differently in terms of thickness, coverage, age, formation history. The weather is different each year too. In fact, everything is different every year. Even where slopes line up, they can be lining up for completely different reasons. No method so far is capable of capturing the eventual outcome, mine is certainly no different.

We are in uncharted territory here, but there's no harm is playing with the data a bit!

42
Arctic sea ice / Re: The 2020 melting season
« on: July 21, 2020, 04:18:58 PM »
Latest simple projection has 7 of the last 20 melt seasons causing a record low, and the 10 year average melt gives a low of 3.53 million km2. Slowest melt (2001) gives a low of 4.39 million km2.

43
Arctic sea ice / Re: Arctic Image of the Day
« on: July 21, 2020, 01:23:21 AM »
Something I put together earlier from the New Siberian Island.

Slightly higher res version on my twitter:
https://twitter.com/Icy_Samuel/status/1285324472724213761

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Arctic sea ice / Re: The 2020 melting season
« on: July 21, 2020, 12:30:43 AM »
ECM want to send some heat over the remaining thick ice at the end of the week. 2020 is relentless.

45
Arctic sea ice / Re: The 2020 melting season
« on: July 19, 2020, 05:42:05 PM »
Latest projection has 7 of the last 20 years beating 2012, and the 10 year average melt reaching a low of 3.56 million km2

46
Despite remaining in roughly 4th lowest position since the last update, the gap to the lowest volume continues to shrink.




47
Arctic sea ice / Re: The 2020 melting season
« on: July 18, 2020, 01:52:34 PM »
The ensemble probability maps (animated below for 120 to 192 hours out) are now showing a high risk of strong winds (>50km/h) around the Arctic from 5 days out. These kinds of maps can be more informative than looking at individual model runs when assessing the probability of storms and such.

48
Arctic sea ice / Re: The 2020 melting season
« on: July 17, 2020, 04:45:14 PM »
After the latest NSIDC extent update, we're now below the minima of 4 additional years, '82, '86, '92 and '96.

All but 2 of the last 20 melt seasons would put the 2020 minimum at least 2nd lowest on record.

The average extent loss of the last 10 years would produce a minimum of 3.64 million km2


49
Arctic sea ice / Re: The 2020 melting season
« on: July 17, 2020, 11:30:58 AM »
With the NSIDC data updated, we've seen a drop of 2.257 million km2 since June 30th, this is a record for that time period, with the next lowest being 2007 with 1.951 million. It's also a record in terms of the % dropped, 23.9% , much higher than the next largest, 20.2% in 2011. Incredible changes.

Will PIOMAS join in on the dramatics, I wonder?

50
Arctic sea ice / Re: The 2020 melting season
« on: July 16, 2020, 11:11:43 PM »
Attached is a gif (quite big ~9.7mb), showing the projections of the 2020 NSIDC extent using the extent losses of the last 20 years, and starting in March. Unfortunately, the NSIDC data hasn't updated since the 12th, so I'm fascinated to see how it looks now!

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